title: Protecting-group-free synthesis as an opportunity for invention.
abstract: The constant pressure to prepare compounds in a more efficient manner has placed the process by which traditional synthetic chemistry is conducted under scrutiny. Areas that have the potential to be improved must be highlighted and modified, so that we can approach the criterion of the 'ideal synthesis'. One area that offers this prospect is the minimization of the use of protecting groups in synthesis. A protection/deprotection event introduces at least two steps into a sequence, incurring costs from additional reagents and waste disposal, and generally leads to a reduced overall yield. Here we present relevant historical context and highlight recent (post-2004) total syntheses that have developed new chemistry in an effort to exclude protecting groups. The invention of chemoselective methodologies is crucial to the execution of 'protecting-group-free' synthesis, and recent advances in this area are also highlighted.
authors.affiliation: Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA.
authors.forename: Ian S
authors.initials: IS
authors.lastname: Young
authors.forename: Phil S
authors.initials: PS
authors.lastname: Baran
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry; D001688:Biological Products / Q000138:chemical synthesis / Q000737:chemistry; D040761:Biomimetic Materials / Q000138:chemical synthesis / Q000737:chemistry; D004224:Diterpenes / Q000138:chemical synthesis / Q000737:chemistry; D009930:Organic Chemicals / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000470:Alkaloids; D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D001688:Biological Products; D004224:Diterpenes; D009930:Organic Chemicals